Monday, 8 July 2013

Russian Meteor Heard Round World Twice

The meteor that exploded over Chelyabinsk, Russia on February 15, 2013 was so powerful that it sent out ultra-low frequency soundwaves that traveled around the world at least twice, according to new research published in the journal Geophysical Research Letters.

The meteor was estimated to be 17 meters (56 feet) in diameter and it weighed about 10,000 metric tons. It entered Earth’s atmosphere and approached Russia traveling at speeds near 20 kilometers per second (45,000 miles per hour). The meteor eventually exploded 19 to 24 kilometers (12 to 15 miles) above Earth’s surface. The shockwave from the explosion shattered windows and damaged buildings in nearby cities.

New analyses of data collected by a global network of 20 infrasound sensors indicate that some ultra-low frequency soundwaves from the explosion circled around the globe at least twice. Infrasound refers to low frequency sound that is below 20 Hz (Hertz) or 20 cycles per second. While humans are incapable of hearing infrasound, these soundwaves travel long distances and some animals such as whales and elephants can use this type of sound for communication purposes.